According to theistic evolutionists, at what point did humans evolve enough to be considered special to God?

From the Roman Catholic point of view, the answer is very simple: when God created man, i.e. when God infused a spiritual soul in two individuals. If there is a spiritual soul, there is abstract reasoning - including true human speech as described e.g. by Chomsky's universal grammar -, moral sense, etc.

BTW, Genesis provides a clear basis for divine creation ex nihilo of each spiritual soul: the verb bara (Strong 1254), "create", as distinct from asah (Strong 6213), "make". Bara indicates the exclusively divine action of creating something which is not the result of reshaping a preexisting entity, and is used, as bārā or wayyiḇrā, in:

• 1:1 & 2:3 for the whole universe;
• 1:21 for the sea animals, the first living beings from the viewpoint of the Hebrews (for whom plants did not count as such);
• 1:27 (& Deut 4:32) for man.

Thus, while sea animals are "created", meaning that their being does not come from mere reshaping of preexistent inanimate matter (since for the Hebrews plants did not count as living beings), birds and land animals are "made", meaning that their being comes through the reshaping of sea animals (which BTW was just the actual case according to contemporary natural science). Man, in turn, is also "created", meaning that his being (i.e. his spiritual soul) does not come through the reshaping of an existing animal.

Now, in Roman Catholic theology theological sentences have one of several degrees of certainty, which from higher to lower are: de fide, fidei proxima, certa, communis, and probabilis. Using these degrees:

It is not even sententia communis whether the infusion of the spiritual soul of the first two human beings happened at the time of their conception or later. For all subsequent human beings, it is sententia certa that it happens at the time of their conception. (In particular, Aristotelian "delayed hominization" is not compatible with Roman Catholic Magisterium, pace St. Thomas Aquinas).

It is also not even sententia communis whether the first two human beings were the only two specimens of a new biological species or were part of a larger population. To note, if the latter was the case, the other members of such population, lacking a spiritual soul, would not have been human beings.

It is sententia fidei proxima that all human beings descend patrilineally from the first man, biblical Adam. Which is in agreement with the observational evidence, through Y chromosome, that all extant men have one patrilineal Most Recent Common Ancestor (MRCA), dubbed Y-Chromosomal Adam. Therefore, biblical Adam must be either Y-Chromosomal Adam or a patrilineal ancestor thereof.

It is sententia de fide that the first man disobeyed God and lost, for him and his descendants, the supernatural gifts that he had received from God.

I hold multiple views on creation. My personal view under the assumption that human evolution occurred in a Darwinian manner descending from apes is that humanity existed in a non-image of God state (no spirit) prior to Adam and Eve. There is some Biblical support for this. Genesis 4:13 indicates that when Cain was sent away, he indicates that whoever finds him will kill him, but who else was there? Further, it says in verse 26 that at that time people began to call on the Lord. Then in chapter 6, verse 1 indicates that the sons of God saw that the daughters of humans were beautiful and they married any of them they chose.

It is possible that there was a more animalistic version of humanity which the descendants of Adam and Eve interbred with and that Adam and Eve were the introduction of a human spirit in the image of God rather than the simple flesh and blood creature. Then with the flood, only those who had bred into the descendants of Adam and Eve would have remained since Noah was part of that line.

Ultimately, since Genesis makes no attempt to be a history book, it leaves a lot of questions unanswered, so it's really all just theories based on fragments of information and particular phrasings that may or may not be valid interpretation. Thus I give this theory with the caveat that it should be taken with a large grain of salt and regarded as just that. A theory.